Strings
by LeaderLeo
Summary: Leo has always been the one with the most pressure, mostly because he was the only one of the four that could handle all of it. The others know they can trust him. But one day, when that pressure threatens to break him...
1. Chapter 1

**Disclaimer: TMNT does not belong to me. (I mean, I'm _thirteen!_)**

"Leo, this is all your fault! You surprised Mikey by opening the door so loudly!"

"MY fault?! How is this my fault? You were the one who told Mikey to help out Donnie, remember Raph?"

"That's cause he was bothering me!"

"Yeah, but Mikey bothering you is better than him spilling chemicals all over Donnie's laptop, like what happened around 30 seconds ago!"

Master Splinter sighed as he listened to Raphael and Leonardo argue yet AGAIN. Lately, many of these arguments had erupted, and although Raph usually came out on top because Donatello and Michelangelo frequently supported him, Splinter was beginning to see the strain on his eldest son.

As a sensei, he knew how the mind worked. When a person was born, there were many, many strings that the brain had. Not physically, but _mentally_. You see, every single time a stressful event happened to a person, a string, sometimes multiple, would snap. When all the strings snapped, the person would beginning to lose himself, starting to lose feeling for all of the people around him, and then eventually turn what most people would call _evil. _Luckily, people generally started out with many strings. However, Splinter was beginning to think that Leonardo was beginning to lose his own sanity. Was it possible?

"No," he murmured, "What am I thinking? No, it is impossible, Leo is too strong, too wise to break all his strings. Why am I to worry?" And then, fully reassured, the great ninjitsu master stood up and walked out of his room.

What none of them, even Leo himself, had realized was that the danger was already happening. Every single time stress had been felt by the leader, physical or mental, many of his strings had snapped.

Many months ago…

"You just let him go?!"

"He wasn't exactly a threat. They'd had enough."

"Wasn't a threat? Dude, he was beating up a blind guy! There's no enough. Now they're gonna think we were too weak to finish the job!"

_Snap._

And later on…

"And the award for worst leader goes to-"

"How am I the worst leader?"

_Snap._

And even later…

"What?! So you're not even going to beat this thing? You created it!"

"I'll let the heroes handle it."

"I TRUSTED YOU!"

"I know, that's messed up, right?"

_Snappity-Snap-Snap._

And every other time in the past year: every time Raph refused to follow his orders, or when Karai was taken by Tigerclaw, when he was stabbed by Shredder, or when he was recovering back in the O'Neil farmhouse with the other turtles, April and Casey.

_Snap. Snap. snap. Snappity-snap._

And finally, the true danger inside was that Leonardo only had three strings left.


	2. Chapter 2

_Tap-tap-tap-tap. Whoosh. Splash! Tap-tap-tap-tap-CLANG!_

"Whoops, sorry, guys." Mikey said as the other three glared at him angrily. "What part of 'night patrol' do you not get? Maybe you forgot about the fact that we're supposed to be completely silent!?" yelled Raph. "You're not so quiet yourself," Donnie smirked. "Guys, shhh. There's the Purple Dragons." Leo hissed, right before Raph was about to knock the purple clad genius's lights out. "Lucky," Raph muttered, while Donnie's smile turned a few levels brighter.

"Alright, you got the tech?" Fong, the leader of the Purple Dragons, asked at the small group beside him. "Good? Okay, let's move." Then the Dragons ran away from the small computer store.

"Okay, let's not move until we know who they have with them." Leo instructed, only to have Raph make a disgusted face. "What? No, we attack them right now before they can get away." "But we can stand a better chance if we know who they have with them." "But we can stop them faster if we do it MY WAY!" "But it might not be successful if we do it YOUR WAY!" The brothers continued bickering, when the Purple Dragons started hearing them. "The Turtles! Let's get out of here," Fong said, and the gang raced away.

Leo and Raph continued arguing for another few seconds, before Leo noticed that the Dragons had gotten away. "Great job, Raph, while you've been questioning my orders for the past few moments, the real enemy got away!" "Well if they did then I guess it's all your fault!" Raph snapped. This irritated the leader _extremely_. Why did Raph have to blame him all the time? None of them got it. Raph, always whining that _he _was the one that was misunderstood, that he should be leader.

_Snap._

Mikey, with his constant pranks that were nothing but annoying and his carefree, no, _careless_ manner in life. Who had never understood or felt the weight of responsibibilty because of being the youngest.

_Snap._

Donnie, always caring only about his inventions and Timothy and pretty _April_, those being the only things he ever felt responsible for, but then again, he hadn't done a great job of taking care of them, had he? Most of his inventions got destroyed, Timothy got mutated, and April almost followed the same fate!

_Stretch….._

Why did he have to always be the responsible one when they always fooled around and never seemed to care about how he felt? Didn't they know that every single failure, every single mistake was at his cost? His job was hard enough, but now his brothers made it almost impossible. Why couldn't they… _just_… LISTEN!

_Snap!_

Suddenly, Leonardo collapsed. "You okay, Leo?" Raph asked, immediately regretting arguing with his leader. Maybe the stress was too much for him… Leo was still for a solid ten seconds, each one making a deeper sense of dread into Raph's heart, until his brother started coughing violently. Donnie gulped. "We'd better get him back to the lair." Raphael nodded.

Leo was getting worried. It was normal to go into stress while arguing with the red clad turtle, in fact, it was almost expected. But he had never went into this kind of seizure before. He felt like he was turning to ice. _What's happening?_

The other three turtles had just helped Leo get back to the lair when he suddenly stopped sputtering. "I feel…fine."

"Maybe, but you still need to get checked up." Donnie replied, looking into his documentaries to search for the possible cure. "No, really. I feel great," the leader said, backing up into his room. "Leo, come back here now!" he heard Raph say. That was it.

Leo turned, his eyes flashing blue. "I TOLD YOU, I'M FINE!" He screamed.

Everyone was stunned. Their older brother had always been the responsible one, the one that never lost his cool, the one who was always trying to pan it down. He had never released an outburst like that over a simple disagreement. However, Raphael refused to back down. "Dude, tell us what's wrong. We can help you."

Patience at an end, Leonardo raced towards his brother with ferocity, then raked the claws that had somehow appeared on his hands down his younger brother's face.

As Mikey's mouth dropped open, Donnie tried to recover himself. This... this didn't make sense! All the science and logic he had learned defied what he had just witnessed. If he had been correct, his older brother had just grew silvery claws, ran over to Raphael at the speed of light, then attacked him, physically. _This should be impossible..._

Raph was getting confused. Everything was a blur. What had just happened? He seemed to remember Leo scratching him with- _Were those claws?_\- but that couldn't have happened. Leo would never have done that, right? It was impossible. Purely impossible.

Meanwhile, Leo shook his head, disoriented. Although the claws were already disappearing, the situation was too much for him understand. What's going on? He remembered Raph yelling at him, and he had lost his temper. But… What was with the claw marks on Raph's face? How had he gotten so hurt? And why were Mikey and Donnie looking at him like that?

"You…you… you grew claws, Leo. Metallic, gleaming claws. I mean, they looked more like gloves… and you looked like a totally different person… and then… YOU ATTACKED RAPH!" Donatello started freaking out. "It's… it's just an illusion, right, just a joke?" Mikey asked, trembling. Leo looked around him for a few moments, processing this new information. Since when did he start growing claws and losing his temper? If not for the scratches, he would have not believed it. However, he knew that he had to calm down Mikey, Donnie, and Raph before they started to break down. "Yeah…yeah, just a joke Mikey. I got a little angry and punched Raph. As for the scratches... Maybe he got hurt during the patrol. The claws weren't real." Mikey sighed with relief and turned away. His brother didn't believe it. Donnie was beginning to clam down, saying, "Come on, Raph, I'll fix you up." Even the red masked turtle was beginning to believe the explanation.

Mikey looked back at his leader, then back at Raph. Although he had to agree that Raph's injury was a bit harsh, he was bound to get hurt someday, accounting all the fights he got into. Mikey mouthed a quick "It's okay", then walked after his brother. It was alright. If Leo said it wasn't real, it wasn't real. So it couldn't have existed.

However, the leader's eyes told the true story.

**Wow, this is coming out WAYYY better than I expected, I thought I would totally mess it up... :D**


	3. Chapter 3

_Poof! Bam…BOOM!_

Donatello coughed hard, his lungs burning from the smoke. "Ugh, what went wrong?" he muttered as he went over a mental checklist inside his head. He checked all of the various gadgets he had used to attempt making the new, more eco friendly retro mutagen, considering the old one had nearly killed Master Splinter's tree. "Oh… I calculated the simmering time wrong, didn't I…"

Sighing, he collapsed into a chair, having no doubt why he had made so many mistakes in the past few days. He was worrying about Leo again.

The leader seemed somewhat disturbed. Whenever Mikey teased him or made one of his cute but stupid jokes, he would lash out at him, shouting at him to shut up before locking himself in his room for a good ten minutes. When Raph was sparring with him and trash talked like he always did, Leo would respond by sending him to the other side of the room. Whenever Donnie asked him with help on an experiment, he would snap at him to ask someone else, he was busy.

Leo would even sometimes complain to Master Splinter, starting intense arguments where he would end up slamming the door to his room and Splinter would end up meditating for hours on end.

There were very few things that would worry Donnie when he was in the middle of a project. But he was starting to feel scared for his older brother.

Leo was training in the dojo when he heard Splinter call his name. "Leonardo! I would like to talk to you, please." _What now..._ He had a strong urge to protest, but even he knew that something was wrong with him, that maybe he could sort it out with his father. So he went.

Once inside, Splinter said, "Leonardo, I realize that you have been acting strangely. Is there something you would like to tell me?" He though hard for a few moments. "No, at least…not anything that could show why I'm acting this way…" Splinter was silent for a few moments, and then asked, "Why don't we meditate on the matter for a few hours?" Leo considered it. "Of course."

They both went into a meditative position. After about thirty minutes, Splinter realized that there was something off about his son's spirit. "What is wrong with him… wait… the strings!" The ninja master quickly analyzed his student's condition, only to find all of them snapped. "This…this is serious… It is much too damaged, I don't think he'll ever be the same again! It's all my fault for not warning him, for ignoring the possible dangers…" Hamato Yoshi stopped muttering when he noticed Leonardo staring at him.

"Is there something wrong, Sensei?" he asked, concerned. "Ah… Nothing, Leonardo. I just…I realized that it is time for training." _I know my son. He would panic or blame himself once he knows that he could possibly hurt the family. It is best not to tell him…yet._

Once they were in the dojo, the sensei put together sparring groups. "Michelangelo versus Leonardo. Raphael versus Donatello. Hajime!"

The sparring matches proved interesting. Donatello managed to win against Raphael, as he used Raph's own sais to unbalance him. Splinter wasn't surprised that he would try to use a successful technique rather than his more physical strengths.

Meanwhile, Michelangelo apparently took this as one of the few matches he took seriously. It was an intense fight, and Master Splinter noticed that Leo had begun to have occasional spasms. _Please lose soon, Michelangelo, or you may get more than you bargained for._ Splinter looked on with a rapidly beating heart.

In the end, Mikey did lose, but by then his opponent seemed to be completely struggling with himself. "Its okay, Mikey you tried your best." He reassured, until his face suddenly switched over completely, into a sneer. "You're so slow, Mikey. No wonder you lost." Then he switched over again. "No…wait…Ugh! I'll be in my room." And he quickly dismissed himself.

Meanwhile, Mikey was annoyed. It was true that Leo won almost every round with him (when he was actually _fighting_, anyway). However, he had never rubbed it in like that before. _Okay, then. Time for a little prank._ Giggling, he put on his infamous Dr. Prankenstein grin.

Leo had never been this nervous. During that match, he hadn't felt well; he had continued to feel that cold, icy sensation he had had for the past week. Then he got this weird kind of feeling, like he was losing control of something. This eventually led to snap at Mikey. And before the training session, with Sensei looking paler than the cheese on Mikey's pizza, what was with that? _I've had enough of all this confusion. I have to ask him._

After steeling himself and taking a few deep breaths as to not lose control again, Leo stepped outside his bedroom door, only to be met with a water balloon to the face, splashing cold water all over him.

"Dr. Prankenstein's payback time!" Mikey laughed as he pulled out a second balloon.

Annoyance was expected; in fact, that was almost the whole point to Mikey's pranks. However, this time, along with the irritation came that terrible cold feeling again, like an icy claw down his back.

Mikey was in the middle of aiming when he noticed a change over his older brother. His face was now contorted into a hateful mask, his eyes glazed over with fury. Mikey had just started thinking, _Did I make him that angry? The prank wasn't supposed to be that bad… _when the eldest ran to the youngest at an unnatural speed, then punched him with the new silver claws that had appeared on his hand and feet.

Michelangelo fell down, shocked. Those claws…they were the same claws from last week! _ Then…that means that all of the things that happened last week, everything…_ "IT WAS ALL REAL!? BUT YOU TOLD ME IT WASN'T!" he yelped, causing Donatello, Raphael, and Master Splinter to run into the room.

They were just in time to witness Leonardo pulling out his now black and silver katana and stab their youngest brother.


	4. Chapter 4

**I know that I said I would post this Thursday at the latest, but I just couldn't help myself, so here it is :)**

Michelangelo gasped as the cold metal pierced his body. The sound that came when Leonardo pulled the blade out was horrible, a long, scraping kind of noise , like two pieces of metal getting scraped together.

He tried to make some kind of noise, any noise, to convince himself that he would be okay, but no sound came from his lips as he fell toward the floor.

Leo pulled the sword out of Mikey, then lifted his head back and let out a laugh, but it wasn't one of those comical mwah-hah-hah laughs. This one was almost his regular one, but instead of being reassuring, it sent a chill through everyone. He then turned to look at his other three family members, grinning crazily with a mad glint in his eye.

He held that stance for roughly two seconds before doubling over, coughing and hacking. When he lifted his head, his swords were back to normal, as were his hands and feet. It was then that all three rushed forward.

Leo felt dazed for a few moments, then his eyes began to focus. Donnie was murmuring "It's okay, it's only in the shoulder. You're gonna be okay, Mikey." Raph was trying to help him up, and Master Splinter just stood in the back, with a strange expression on his face. _Was that guilt? Why? Whatever I did, it's my fault, isn't it? Besides, it can't be that-_

He went brain-dead when he placed his eyes on Mikey, moaning and slipping slowly into unconsciousness. "Oh my gosh, oh my gosh…" he muttered, stumbling back a few feet. Mikey had been stabbed! But what had happened? Who had done…_ wait. _He knew exactly who had done it. Leo's answer was confirmed by the other members of his family, who were backing away from him, slowly. Raphael was even stepping in front of Michelangelo, guarding him. "Get away from him."

Those words shattered any bit of doubt Leonardo had left. He was becoming insane. He had slowly suspected it for the past few days, but this completely proved it. His brothers and sensei were right to be afraid. He could lunge at them, hurt them at any moment, possibly even…

He knew what he had to do. Leonardo turned around and started running, as fast as he could, away from his family.

He had just made it halfway out of the sewers when he heard Splinter, calling for him to stop. Hesitating, Leo slowed down, then resumed his pace, but even faster than before. However, he didn't make it far until his hand was grasped by his father.

"Leonardo," Hamato Yoshi said, "come back, we need you. Your brothers need you. How are they going to survive without a leader?"

"They have a better chance of surviving if they have no leader instead of a crazy one."

"No! You are NOT insane. It was because of the strings! Remember how I told you about them a few months ago, during a lesson? Leonardo, your strings have snapped. All of them. I knew but I didn't tell you, fearing that you would panic. This is all my fault. Come back home with me!"

Leo staggered back, like he had taken a blow. He knew, under all the pressure he was constantly under, that a few of them had definitely snapped. All of theirs did. But a person had hundreds, thousands of threads. He didn't expect to lose them all! But if anything, this just made the situation worse.

"Father, didn't you tell me that if all the strings have snapped and the person is insane, that their madness just get stronger and stronger, until it consumes the person?" he asked.

Splinter seemed to hesitate to answer this question. Finally, he replied, choosing his words carefully, "Yes. However, this does not mean that you cannot overcome that. You have a strong mind, Leonardo. Maybe…" He stopped. They both knew the truth.

"Sensei, you know that no one has ever been able to overcome it. Neither can I. Let go of my hand. I'm doing this for our family."

"No, Leonardo. You can stay with us. We just have to be careful." "Sensei, LET GO." "No."

Leo was started to feel annoyed, and just a little bit angry. "I said, LET GO." "Leonardo, we can help you."

The eldest was about to reason with his father, when he started feeling the familiar cold, frosty feeling down his spine. "Father! It's happening again, I'm going crazy. You have to let go, you're agitating me and it's causing me to react. YOU HAVE TO LET GO!"

"Leonardo, I-" "HOW MANY TIMES DO I HAVE TO TELL YOU TO FUCKING LET GO!"

Splinter gasped as his son turned to him, bristling. Before he could react, Leo kicked him in the head, then used to momentum to rip free of his grip. He crashed into a sewer pipe and landed awkwardly, hearing a sharp _snap_ from his ankle. Wincing, he looked up, to see his son staring, with absolute horror in his eyes. "See, that's _exactly_ why I have to go." And with that, he began turning around and sprinting away.

"No…Leonardo…" The last image Splinter saw before blacking out was his eldest son, running away from his family.

Once outside, Leo took a few deep breaths. What he did was for the best. He had already stabbed Mikey in the shoulder, broke Sensei's ankle. It was best to stay away from the rest of them.

He was running from rooftop to rooftop, trying to clear his head, when he had a relapse. But why? It wasn't as if he had been annoyed or angry. Why would he turn insane? It was then that it hit him. The insanity was getting stronger. He would just automatically switch from now on, angry or not. Closing his eyes, he tried to think. Developing at this rate, he would only have about one more chance to be good after this… After that, he would be utterly evil, forever, with no more turning back.

When he opened his eyes, they were gleaming viciously. "Time to get into some _real_ action," he grinned. "And I've got a place in mind."

In the Foot Clan lair, the Shredder was on his throne. "So you are telling me that you haven't been able to track down the Turtles for an entire week?!" he asked Tigerclaw with a disgusted tone in his voice. "No, Master Shredder, but we will keep searching-"

He was interrupted by a loud knock on the door. _Thump-thump-thump._ Tigerclaw looked at Shredder, who shook his head no. "I don't know who this is, and I won't take any chances."

The knock came again, louder this time. _THUMP-THUMP-THUMP._ Again nobody answered. Finally, It began knocking a third time, but this one didn't stop. _THUMP-THUMP-THUMP-THUMP-THUMP-THUMP._ Finally, after fifteen blows, there was a sudden silence. Everyone tensed up, but nothing and no one came through the door. After around twenty seconds everyone started relaxing.

"Probably some child's idea of a joke," Tigerclaw growled. "Hmph. I suppose so." Shredder agreed. "Anyhow, Tigerclaw, continue with your report-"

He was interrupted when the doors flied open.

Quickly everyone drew their weapons, Fishface pulled out his knifes, Rahzar sharpened his claws, Tigerclaw reached for his guns, Karai grasped her tanto, and Shredder slid out his gauntlet blades. If they were expecting an army, they were sorely mistaken.

The doorway revealed a single figure, in the shadows. "Come out and face me! Let us fight this out!" Shredder yelled.

The figure stepped into the light. Leonardo was grinning maliciously, with a wicked glint in his eye.


	5. Chapter 5

**Okay, let me make this clear point so that no one gets confused, because this IS a little confusing. I know that while Karai was still in the Foot as a human girl, Tigerclaw was never sent on any missions besides to capture Splinter and the Turtles, because he got swallowed by a giant worm and carried to another dimension. This is my mistake, as I wanted to include Tigerclaw AND Karai, and I couldn't choose between them. Also, Karai is NOT Splinter's daughter. Sorry for the long confusing explanation. Enjoy :)**

Shredder looked at the figure carefully. "Leonardo?" he asked, his voice full of disbelief.

The former leader was almost unrecognizable. His belts, and wrappings and all been changed to black. The buckles and the katanas were now a sinister silver, probably to match the strange, metallic looking claws on his feet and hands. Finally, he had changed his blue mask for one of a dark, pitch black color. The only giveaway was the deep, ocean blue eyes, but even they had changed from thoughtful, kind, and wise to deadly, intelligent, and insane.

Shredder laughed, and soon the rest of the Foot Clan followed suit. "So, Leonardo, you've decided to change your looks? Well, let me tell you that a few new accessories will not help you succeed any more against the Foot."

Leo grinned. "Oh, I've got a little more than a few new accessories." Shredder raised an eyebrow. "How so?" "Why don't you come and find out."

Shredder smiled. "Challenge accepted. Foot Bots, ATTACK!"

Leo calmly waited the few seconds that it took for the Bots to arrive. When the first attempted to decapitate him, he swung under the blade, then used the momentum to knock it down, which as a chain reaction, knocked down the ten others behind it. After seeing this move, the Foot Bots learned his fighting style and rushed towards him once again. Right when it looked like he was going to reuse the style, he backflipped, dodging about twenty attacks, and used a move from a completely different technique.

Shredder gaped at the scene in front of him, his mouth hanging open behind his helmet. Leonardo was dropping his thousand-bot-army like flies! Anger overcoming his surprise, he pointed at the turtle, surrounded by around five remaining robots, and ordered, "FOOT CLAN, ATTACK!" Quickly, Rahzar and Fishface, quickly followed by Tigerclaw and Karai, lunged for the ninja.

Meanwhile, Leonardo was having the time of his life. His insanity made him stronger, faster, better than he had ever been before. Although he knew that attacking one of the most dangerous ninja clans in the world was a crazy idea, hey, he was crazy. Not to mention, this wasn't just for fun. He had a certain plan in mind, and this was the first step.

He was just finishing off the last Foot Bot when out of the corner of his eye, he saw Rahzar coming from the left, Fishface from the right. He knew just what to do. Taking a brisk step backwards, Leonardo avoided both attacks, and as a double, the two idiots slammed into each other. He jumped about five meters up in the air while doing a flip, then came to land on their heads, smashing them to the floor and knocking them out.

Tigerclaw and Karai quickly took their places, however, by jumping from the ceiling and successfully pinning him to the floor. Tigerclaw drew his sword and brought it down… right where Leonardo was half a second ago. By the time he looked up, the turtle was performing a spinning kick in the air, which promptly smacked into Karai's face.

Tigerclaw ran for him, and strangely, Leo was just standing straight and still, not even reaching for his swords. _Why isn't he moving? The little son of a bitch thinks he's too good for me?_

The large cat got his answer when, right before he reached the teen, his world was suddenly spinning, around and around. He realized what had happened. Leo had kicked his legs with such force that he had done an accidental flip in the air. _Wait. If I'm up in the air, that means that-_

And he indeed did go crashing down, smashing his face into the floor and blacking out, like his three other partners had done.

Leonardo then turned to the Shredder, enjoying the moment of victory and also Shredder's incredibly stupid expression.

Oroku Saki gaped, openmouthed, for a good 10 seconds. Finally, he recovered himself. "Impressive," he managed to get out. "But certainly not good enough to defeat me." The lie nearly choked him on its way out, he was still getting over the fact that the mutant had won against the whole Foot Clan, save for himself.

Getting up, the Shredder slowly slid out his blades. The two opponents stared at each other, one testy, and the other confident. By now, the remaining members of the Foot had woken up and placed themselves in a position where they could not interfere in the fight; they all knew that they wouldn't be much help.

Without a single warning, the two leaders ran at each other, both aiming to kill. At the last moment, Leo jumped and did a perfect spinning kick, calculated to not only hit but also to slash him with the claws. As soon as Shredder got up, he went down again almost immediately.

Finally, Leonardo let him get back up for good. Panting, the Shredder lunged at him again, but the teen grabbed the gauntlet blades. They didn't even seem to hurt him. With a small twist, the metal broke, then clattered to the floor.

From then on, Shredder barely even had time to touch the floor. Not even 20 seconds later, he found himself on the floor, staring at a katana blade.

"Too easy," Leo grinned. "Now prepare to-"

He fell off the Shredder, gasping and groaning. When he looked up and focused on the settings around him, his expression turned into that of deep despair. _I know him. My dark side. His goal is to destroy the Hamato Clan, the ones who have caused me so much pain. But to do that, he needs a bigger, larger force… And there are fewer forces bigger and larger than the Foot Clan._

Reviewing his calculations from the last time he was truly sane, he remembered another fact. This was the last time anyone would ever see the old Leonardo, ever. A single tear soaked into the black mask and rolled down his cheek. This was the last time he would be himself, and his father and brothers weren't here to see it.

He heard a sound right behind him, and he turned to face the Shredder, who was holding the katana that he had dropped earlier. "I don't know what happened to you, or why you have changed so much. But I don't care. THIS ENDS NOW!"

Rushing towards the turtle, he raised the sword. Leo barely dodged it. He turned to the Shredder, and their eyes met.

However, the blue pair, which had shown so much fear and sadness only moments ago, were now sparkling with determination. If this was to be his last chance at goodness, he could use it to save a life.

"Listen, Shredder!" He yelled. "Stop attacking me! It's going to cause me to go on the defensive and turn insane again! And this time, I'm not going to change back! You and I both know that when in my evil state, a fight to the death will be a fight I will win. I don't want to kill you, not yet. I don't want this to be an unfair victory that is not shared by my family. This is for the good of both of us. Stop attacking me and get out of here!"

Shredder considered this, and for a moment, Leo thought that he had convinced him. However, he knew he had failed when the Shredder responded, "You started this by coming into my lair. You're just too scared to finish it." With that, he raced towards the turtle, clashing swords.

"No, listen! You've got to believe me! You have to-"

He was cut short when there was a burning pain in his arm. He looked to see that the Shredder had stabbed it. It wasn't fatal, but it was deep enough for his vision to start spinning, and he collapsed.

"Now can you say who is going to win?" The Foot leader stepped forward and pushed the blade down.

But it was caught.

Smirking at him, the dark side of his enemy was grasping the blade firmly in his hands. He then pulled the sword out of his hands and firmly stabbed the Shredder. Oroku Saki, at first, looked as though he had not believed it, as if he had not been stabbed through the heart. As Leonardo pulled out the katana, the Shredder collapsed, completely still.

There was very little blood, just a small stream trickling from his mouth. One might have even thought that he had simply tripped and hit his face.

The Foot Clan was completely silent, staring at their leader's killer. Then Karai shouted, "Father!" The girl pulled out her own blade, ready to avenge her beloved Shredder, shen she felt a hand on her shoulder. Tigerclaw growled in her ear, "Do you want to get killed?" Knowing that the overgrown cat was right, she slowly replaced her tanto. _You'll pay. One day, you'll pay._

After a whole minute of silence, Fishface began to speak, cautiously. "So, who's our new leader?" This caused the whole clan to erupt with arguments. The new leadership role was a once- in- a-lifetime chance. No one wanted to miss it.

"Foot Clan, silence." A single, icy voice rang through the building, and everyone immediately followed the order. "You all try to come up with petty arguments, acting like children. However, can anyone say that you have defeated the Shredder?" Leonardo challenged. No one answered. "I thought so. Therefore, I am your new leader. Any comments?"

When no one disagreed, he perched himself on the throne, dark eyes gleaming with success. Tigerclaw spoke. "Then what is our new goal, Leon- err, Master Shredder?"

Leonardo grinned, his expression showing equal hints of experience, power, and madness. "What it always has been. To destroy the Hamato Clan."

**Wow, this was my longest chapter yet... But that's not much, considering that I've only uploaded 5...**


	6. Chapter 6

Karai was playing games on her phone when she heard a tap on her bedroom door.

"If it's Fishface, get me some water. If it's Rahzar, no, we are not sparring again, you may as well give up trying to beat me. If it's Tigerclaw, get out of here. With that said, come in."

The door opened, and Leonardo glared at the kunoichi. "Oh, and if it's you, then…. Hi." Karai mumbled.

"Karai, I and the others have called your name more than five times. There is a clan meeting!" "Sorry, I'll be right there," she said, getting up. _Bossing us around like we're your little soldiers…I'll make you regret all of this, even if it costs me everything._

At the meeting, Leo announced, "I have decided our next plan of action. I know that April O'Neil always passes by Murakami's restaurant when she's on solo patrols, which is quite often. We'll give her a little message that she can send to the Turtles. 'We' meaning Tigerclaw, Rahzar, Fishface, and myself, along with quite a few Foot Bots to add to intimidation."

Karai was listening for her name when she realized that its wasn't there. "What!? I'm not going!?" "No, you'll stay here and guard the lair." The girl growled. Both she and her current leader knew very well that the lair had a chance of below 1% of getting attacked by anyone. This choice of who does what had been directed at her on purpose, planned carefully to cause a reaction out of her, or more specifically, to make her feel annoyed.

"Fine." She responded nonchalantly. _Soon, it's going to be me with all the control. You'll see._

"Alright, Foot Clan, let's move!" The Shredder called, then with the others, left the building.

On the roof of Murakami's restaurant, April was texting on her phone. _Hey, D. _She waited for a reply. She received a response rather quickly, from Donatello:_ What's your status? Have you found Leo yet? _She replied:_No, but I'm still searching. _Five minutes later, April sighed. _Nothing.__ I'll be returning to the lair._ She tucked her T- phone into her pocket and turned around. She was lucky not to smack her face right into Tigerclaw.

"What the- Okay, you wanna do this?" She pulled out her tessen and was getting into a fighting stance when out of the corner of her eye, she noticed Fishface, stepping out into the light. _Oh shit. I can't fight both of them. _Things got worse when Rahzar and some footbots joined the group. Swallowing down her panic, she asked, "So, the whole Foot, huh? Where's Shredder?"

At this all of them flinched, then regained their composure. "We…have a new Master Shredder." Tigerclaw said. "The old one is gone."

April stepped back. A New Shredder? Obviously the old one had died, probably disposed of by this new Shredder. And that meant that this new one would be even more dangerous. _This is totally my worst day…_

"Wh-who's your new master?" At this Tigerclaw grinned, and stepped back. A figure dropped down in front of her so fast that April could barely see it. With a shock, she realized who she was looking at.

"L-Leo?"

"Nice to meet you again, Ms. O'Neil," he smirked. He looked so different. There was a bandage wrapped around his arm, probably from the fight with the Shredder. He was now all in black and silver, and although those claws that Donnie had told her about were currently nowhere in sight, she had no doubt that they would reappear when he was in combat or danger.

"L-Leo… _Why?_"

He could hear the betrayal, the hurt in her voice. That was normal. The old Leo had been able to do this, and come to someone's aid because he knew when something was wrong. No, the twisted fact was that he liked it. He had surprised her, had scared her, and he enjoyed it.

"Tell the rest of the Hamato Clan that they have a new enemy to reckon with. When you and the others come for battle," he grinned. "I'll be ready."

He and the rest of the Foot swooped off of the rooftop, and April grabbed her phone.

Donatello was working on the batch of Retromutagen. He was close, and he knew it. But the machine he needed to complete it had to be powered by a Kraang power cell, so now there he was, arguing with Raphael, with Michelangelo watching the fight.

"We need to go out there and get that power cell!"

"No, we need to go out there are look for Leo!"

"We're doing that tonight anyway, can't we just do this one thing?"

"It's too dangerous!"

"Since when did you go from making Leo crazy to the one who's acting just like him!? I mean-"

Donnie stopped short when he heard the T-Phone ring in his belt. Picking it up and looking at the screen, he felt himself turn pink. The other two teens, knowing exactly who it was, starting smiling. "April?" He asked. The answer he received wasn't what he was expecting.

"Donnie! I have to tell you something! It's about Leo."

"What? Is there something wrong? Did you find him?"

"Yeah, and… he's apparently killed the Shredder."

Donnie was confused. _Isn't that good?_

"And I know that you might think that that's a good thing, but it's not, he's the new Shredder! And he basically wants to have a war or something, and, based on what he told me, pretty soon. And, and…" April couldn't help it. The words just kept tumbling out until she bit her tongue to shut herself up.

Donatello was silent at first, then spoke up.

"Our brother wants to see us, then we'll go."

**I know I haven't updated in a while, sorry…. **


	7. Chapter 7

Michelangelo was writing in his diary (yes, he had one).

_September 18th, 2012_

_My shoulder is almost as good as new. It's been a month, and the wound wasn't that deep. I wish I can say the same thing about my family. Sensei has been meditating a lot more than usual, and Donnie is acting really depressed. Raph is getting a lot more angrier than usual…If that's even possible. Recently, Donnie got a text from April, aka his GIRLFRIEND. Leo's actually the new Shredder! Eeeeyup. That's right. I mean, I was like, Crazy? Okay. Evil? Acceptable. But the Shredder? WHAT!? He hates the Shredder and pretty much the entire Foot Clan! But then he becomes the leader? What?! Anyway, so Leo wants to have this kinda battle or whatever to finish it out. And usually, I leave this kinda stuff to the more older, boring members of the clan. But this time, since it's also my problem too because of Leo being a big part in it, I had to participate. So basically, everyone's preparing for the battle ahead. It's not like we're trying to kill him or anything, we're just taking this opportunity to maybe convince him to be not freaky again. It's a small chance, but Donnie says that it's possible, that some people that got therapy managed to regain their mind or something… I stopped listening after that. The battle is tomorrow, so I need to go train…or maybe play like 2 video games first… no wait, Raph's knocking on my door to hurry up, so I need to train first-_

"Raph! Don't come in here! No, I'm not doing anything wrong!" Mikey rapidly stuffed the diary under his pillow and ran out the door.

Donatello hissed as the acid hit his finger. "OWWW! Ugh…" Wiping it on a cloth, he heard the door behind him open and close quietly. Stealthy, sneaking footsteps approached him. Finally, at the last minute, he turned around and pointed his bo staff at the intruder.

"April?" he quickly attempted to recover himself. "N-nice moves! I didn't even know you were there!" April sighed. "Yeah, right. By the time I was two yards' distance from you, I found myself looking at the tip of your blade!" "No, really, you were great!"

April rolled her eyes, sensing her way through the lie. "So, watcha doing?"

"Oh, err, trying to complete a possible weapon we could use against the Foot Clan and maybe even Leo." "I thought you were working on non-environmentally-destroying Retromutagen." "Oh, well, uh, you know. This problem's kind of a… a bigger one than what we were worrying about before."

"Okay….What does the machine do?" she asked, after carefully deciding that the question would be worth the risk of possibly getting just a long and boring lecture. "It freezes the enemies. However, the stronger they are, the less time it holds them." "Like how long?"

He thought about this before answering, "For like, the Purple Dragons? Maybe a full 10 minutes. As for Tigerclaw, probably 10 seconds, if we're lucky. Now, for someone like the Shredder…." He trailed off.

"Maybe half a second?" Donatello smiled down at April, who was obviously trying to fill in the silence. "Yeah, something like that."

She grinned back at him, but all the same, she knew something was wrong. "All right, fess up. What's bothering you?" "Oh, ummm…" Finally, giving in, he responded, "It's about Leo. I mean, I'm pretty much worried about how the battle might turn out. It would most likely end up with one side winning, and no matter which side, it's pretty much bad for us."

April thought this over for a moment. "Hey, look on the bright side. At least we might win, won't we?" "Yeah, sure we can win." He paused, choosing the right words to say. "But there won't be any happy ending."

Raphael glared at the face of the Shredder, or at least, what he used to be before he turned into the Shredder. "Why? Why would you do all of this?"

He knew that to the rest of his family, he might seem a little bonkers. He was yelling at a picture of his former older brother. However, they didn't get it. All of them talking about how they were going to turn Leo back, how he was going to recover to become their leader again. But that wasn't going to happen.

None of them understood it. The old Leo, the brother that they once knew, was gone. It was pretty clear by now that he had made a betrayal so intense that there was no turning back. He used to be the hero who always stood up to his fears, the leader who kept on pushing them on, and the brother who was always there to make it all right. But then, he turned around and completely backstabbed all of them, joining, _no_, becoming the leader of their most hated enemy in history!

However, Raph wasn't blaming Leonardo. That wasn't what he was stressing over, day and night. It was that he was blaming himself.

If he hadn't pushed his brother to the limit, none of this would have happened. Master Splinter wouldn't be depressed, Donnie wouldn't be overworking, Mikey wouldn't be breaking apart trying to put the family back together, and Leo wouldn't be evil.

The normally strong, sure- headed turtle felt dizzy and uncertain. Falling on his bed, he stared at the photo that he always had on the ceiling, to make sure that he looked at it every night before falling asleep.

Donnie's thoughtful dark eyes, Mikey's innocent, light blue ones, Leo's calm, deep blue ones, and his own, electric light green ones. Raph didn't hear it when Splinter came into the room.

"It's not your fault."

The turtle didn't even bother asking how he knew; from his experience, the sensei pretty much found out everything, given enough time. "Yes it is. I snapped the strings, right? I caused the battle, right? It's kinda obvious." "Yes, that's true. You did cause the problem we are in right now. However, no one said that you cannot fix it." At this, Raphael looked up.

"At the fight in the Foot Clan lair tomorrow, help Leonardo. Talk to him, reach him so that he can turn back to his normal self once again." Raph started lightning up until a thought hit him. "Wait, but if I'm the one who got him there in the first place, what will make him even want to listen?"

"Think about it. If you are the one who affected your brother so much, then doesn't that prove that he is going to want to listen to you, evil or not? No matter what side he is in, you will affect him, one way or another." "Oh, that helps…." "Raphael, stop being sarcastic, as you know that it did actually help."

The teen opened his mouth to retort, then closed it. He was right. It did help. Thanks to that little talk, he still knew who was to blame, but also how to fix the situation that they were in. "Thanks Master Splint-" Raph faltered when he noticed that his father was gone. Looking back at the picture on the ceiling, he located the older brother he used to know.

"Don't worry bro, we'll get you back."

**Did you get the Phineas and Ferb reference in Donnie's POV? (It's not really a POV, but I don't really know what to call it)**


	8. Chapter 8

**Sorry, I know I haven't updated in a long time. Basically a lot of exams this week, and I also had a martial arts test (I'm a brown belt XD)**

Leonardo was in a good mood today. Karai had just reported that Splinter and the rest of his little fools were coming, which surprised him since it was 3:00 PM and still pretty bright outside. But then again, he was the one who had requested the battle, and if the Turtles wanted to end their lives while the sun was still setting, he was fine with that.

So when the door slammed open and only April, Casey, and Splinter were present, Leo was more than a little bit disappointed.

"Hamato Yoshi, April, and…" "His name's Casey. Casey Jones." Leo glanced at April, who met his gaze and unknowingly took a step back…behind Casey. Obviously she had some sort of 'connection' with him that Donnie probably disagreed with.

"Well then, Yoshi…I guess you're doing a worse job of staying a secret without my help. If this little _kid _managed to find out about you, how long before the rest of the world?" he laughed.

"Hey, I'm not a little kid, I'm seventeen! And from what I hear, you're only fifteen, so shut up!" Master Shredder turned to the person who had spoken, and _Casey_ defiantly glared back. _Stupid human. You dragged yourself into something you may not come out alive from._ "Enough talk. Although I must say that I'm very disappointed in your sons for not having the mettle to show up, I can deal with you three first. Foot Clan, ATTACK!"

The tension in the throne room rose as Leo watched his soldiers choose their opponents. Tigerclaw, Karai, and Fishface went for Splinter as Rahzar and ten Footbots headed for April. Fifty bots were surrounding Casey. They were bound to lose, especially since he had noticed the two ninjas hiding right above him, thinking that they were unnoticeable.

Raphael and Michelangelo jumped down and grabbed his arms. "Donnie! Fire!" Raphael yelled, and Donatello appeared with the machine, which had already been aimed, and pressed the button. But when he looked up, Leo had dodged, and Mikey was now the frozen one. "Sorry," he yelped, then aimed the cannon again, which was nearly impossible as Raph and Leo were sparring viciously. The current plan was to freeze Leo and possibly other Foot clan members if he had already completed the job. Donnie had calculated that even though at the current moment the Foot Clan leader was almost unstoppable, it was all powered by his severed strings, and he hadn't actually improved by practice. Therefore, since the freeze- ray's effectiveness depended on how 'good' a fighter was _when he had actually earned the skills_, he would be frozen for a good 3 minutes.

He heard an 'oof' from the side, and turned to see that both Casey and April had been captured. Splinter wasn't faring well either, as the dozens of Foot that had been fighting the two teens now swarmed onto him. Finally, after looking aiming the machine around nineteen times with no success, the genius abandoned the weapon and picked up his bo.

Leo was in the middle of totally winning against Raph when he turned to see Donnie running at him. _When will these pests learn that they won't be able to defeat me?_ With that thought in his head, he avoided Donatello and ran for Splinter. _Take the big one down first. Then pay more attention to his students._ As he ran into the frenzy, all the rest of the Foot backed off for their leader. Leo did a spinning kick with the claws that had evolved during the fight. Starting from there, everything went smoothly and Splinter, like the two teens earlier, went down.

Slowly, Leo turned around to face the other three. He opened his mouth to order Tigerclaw to take Donatello down, but when he looked at the mutant, he was frozen in an ice block, along with Fishface, Rahzar, and Karai. "Idiots. I'll do this myself."

He raced toward Donnie and threw a punch to the face, then slammed his elbow onto the top of his head, knocking him out. Facing Mikey, he ran towards his youngest brother. The flying side kick tossed the turtle to the other side of the room. He turned around to see both Donnie and Raph racing for him. "Can't get enough, can you," he taunted. "Okay, then let's play real." He pulled two shuriken out of his belt, then threw them. They were aimed carefully, but not to kill.

Donnie gasped as he felt his leg burning. He looked down to observe the damage. The shuriken had embedded itself inside his leg, around… two inches deep? Feeling lightheaded, he forced his eyes away from the wound, towards Raph, then gasped again in horror.

Raph was similarly studying his arm. The blades had ripped all the way down, tearing through the though skin and making it numb. _Crap. How am I going to fight like this?_ He looked up see his deranged brother, who was making his way toward him. _Okay, then. Time for Plan B._ He raised his head, and began._ Here goes nothing._

"Listen up Leo, I'm not gonna lie. I know we've treated you pretty badly for the past few months. And I'm really sorry about that. 'Cause I know and completely understand that we're the ones who made you like this. We took advantage of your tolerance, your patience, your personality. We're really sorry for that. But I also think that no matter what problem, there's always a solution. And Bro, although we're the ones, _I'm _the one who started this whole mess, we're also going to be the ones to fix it. Right now, you're this evil, crazed, psychomaniac that's trying to destroy us. But that's not you. You're a kind friend, a wise leader, and a caring brother. Not a psychomaniac. I know the real Leo's inside there somewhere. So come out. I know you can do it. 'Cause of there's one thing I know about my big bro, it's that he NEVER GIVES UP!"

This seemed to have no effect on the recipient. "What a heartwarming, useless, speech! Pretty bad choice of words however, considering they're your-" hacking and coughing, he bent over, and within seconds was back up again. But there was something different. _No way… _Leonardo, the leader he had always known, was standing in front of him.

"Raph… help…"

"You can do it! I know you can! Just follow my voice…" Leo seemed to be struggling with the dark side of himself. "SHUT UP!" "Raph!" "Stop it! Stop talking!" "No, keep going!" This continued, the flips getting faster and faster, quicker and quicker, until he heard a voice that belonged to his brother but at the same time didn't, scream, "No! Stop it, stop it!_ Stop it right now!_ NO!"

As for both Leonardos, the world began tilting and then went black.

The black-masked ninja sat up to find three worried faces looking at him. "Leo?" "Dude!" "You're back!" Donatello, Michelangelo, and Raphael helped him up. "NO!" he turned around to see an incredibly dismayed Tigerclaw, while Splinter, April, and some kind of new kid dismantled the rest of the Foot Clan.

"Leo! How do you feel?" "Uhh… fine. I feel great." Everyone smiled at this, and Mikey let out a huge "BOOYAKASHA!" "So, you ready to go back home?" Smiling, he opened his mouth to answer Donnie's question, but a surprised gasp came out instead. As the stunned Hamato Clan watched, their long lost friend and brother collapsed. Then they realized what had happened.

Karai Oroku stood behind the fallen leader, with her blade now streaked with blood. "I told you I'd get you back."


	9. Chapter 9

**Warning: This is a short chapter. I'm also nearing the end of this fanfiction. The last chapter will probably be the one after this…**

When Leonardo collapsed, nobody moved for a full 20 seconds. Then Raph, as usual, dived into action. He attacked Karai viciously, his movements fueled by hate. When the battle finished with Raphael striking her on the head with the handles of his sais and effectively knocking her out, Mikey had to intervene. "Dude, I know you're angry, but this isn't the time. We need to get Leo back and make sure he's okay." His older brother growled, but then relented. "Fine. But I'm not gonna let her off the hook completely."

"That's fine," Mikey soothed. "We're gonna get her back someday, Raph, just not today. Come on, let's go. We don't want them to leave without us." Then he ran outside to help Donnie and April lift Leo into the Shellraiser, which Casey had gone to bring back. On the way back, the little ninja noticed that Raph never left his leader's side.

Meanwhile, Master Splinter stood silently in the back, watching the scene._ My son, this is all my fault..._

They rushed him to the lair, into Donatello's lab. The genius shooed everybody out in order to concentrate, then began to analyze the the damage. He paled upon seeing the results. When he called, they all dashed in. "So how is it, D?" April asked. "Not good. He's losing too much blood. When the blade went in, it also succeeded in bursting a lung… H-he's probably not going to make it." At this, everyone fell silent.

Then Splinter stood up. "But there is a chance, correct?" "Y-yes…" "Then we'll do whatever we can, no matter how much the odds are against us."

So for the next 3 hours, there were only the sound of Donatello's orders, one of them dashing around to follow them, and the occasional coughing from Leo. Donnie was doing all that he could. His plan was to fix the hole in the lung, but it was a race against time. Thanks to the upgraded breathing tube, Leo could still breathe, but breathing would make the damage even worse. The lung would be fine, but because of the movement, he would lose even more blood. The problem was that to fix the lungs, he needed to keep the wound open. So all in all, he would have to fix the lungs _and _seal the actual wound before it either got infected or he lost too much blood. Even if he missed it by less than a second, it would be a lost cause.

Despite all the places the plan could go wrong, it was going well. He had just fixed the popped lung, and was waiting for it to adjust to that he could complete the rest of the operation. This would generally take around thirty minutes, so he took the time to properly heal everyone else's wounds, including himself. However, he could never stray too long from one thought: _Leo, please be alright…_

At 1:00 AM, Raph, Donnie, and Mikey were still working, being the only ones still in the lab. April had fallen asleep at around 12, the battle had obviously been a bit too rough for her. Casey left to bring her home, using the fact that her dad might be worried as an excuse. Splinter went with him to make sure nothing would happen, whether it be Purple Dragons, the Foot Clan, or a kiss. After all, all three events would make Donatello blow a fuse.

Raph was musing over just what would Donnie do if April had actually kissed Casey when his older brother opened his eyes. Without warning, he started convulsing violently. "Guys! Donnie, Mikey! Get over here, SOMETHING'S WRONG!"

The two ninjas rushed into the lab. "What's wr- OMIGOSH! H-his temperature must have been too high! How did I not notice..." Donnie immediately started working on cooling him down. _This whole time while I've been worrying about timing, I completely forgot about keeping a level temperature! I'm such an idiot... _Meanwhile, Mikey and Raph strained to hear what Leo, who had woken up, was trying to say. He had stopped convulsing, and was desperately attempting to form words.

"Raph…Mikey…Donnie…" Leo felt as if time had slowed down. His movements felt clumsy, and every single breath was like trying to breathe underwater. "You have to know that this isn't your faults." "Y-yes it is." Mikey blubbered. "We messed up and made you crazy. If we had actually noticed all the pressure we were giving you, none of us would be having this kind of problem, right?" "No, it's not. You guys fixed it, didn't you?"

"Yeah, but we can't fix this problem, and it's technically our fault too. Karai wouldn't have wanted revenge if we didn't snap all of your strings and cause you to kill the Shredder." Donnie murmured. "It isn't your faults. You did the best you could. You guys shouldn't blame yourselves." "We _did_ the best we _could_? Don't use the past tense Bro, you're gonna make it. We just got you back, we can't lose you." Raph said, feeling desperate.

Leo smiled; he knew he had been lucky to regain his sanity, but he wouldn't be lucky a second time. Then, with the little energy he had left, he ordered, "Promise me that you won't blame yourselves."

Donnie glanced at the heart monitor. The heartbeat was slowing down…"We promise." all of them whispered. "Thank you."

They were the last words he remembered saying before he gave in to the darkness.

As Raphael stared at the heart monitor, the last slight rise and fall of that red line, he knew that he couldn't do it. _I'm sorry, Leo,_ he thought. _I can't keep my promise._


	10. Chapter 10

**Hi everyone, thank you for all the support you gave to Strings. Considering it was my first, I didn't expect it to be this successful. This is the last chapter, but I might make a second fanfic continuing it, depending on how much time I'll have and how many people want a second. ;)**

It had been two days since his brother died.

Raphael looked at the picture on his ceiling. He remembered the last time he had been looking at that picture, when he and the others were preparing to go to war against their brother. He remembered hoping that by the end of that day, Leo would be coming home with them, laughing and joking around as usual.

He never expected this. He never expected that as soon as he had gotten his brother back, that they would lose him again. Why? Why did this have to happen? As he lay back and stared at his brother's face, he thought,

_Leo, I would do anything to hear your voice one last time._

Michelangelo looked at his comic, then threw it down. Nothing was fun anymore. Everyone was so gloomy, and with good reason. Donnie shut himself up in the lab for hours along with Raphael, who did what he had done after the Kraang invasion. He constantly looked over Leo, never leaving his side.

They were currently still hooking him up, as although his heart had stopped, according to Donatello, his brain was still alive. Even though he started arguing with himself about how this wasn't possible, they had decided to continue riding on that miniscule hope. But as the first day moved on, everybody gave up. If he didn't wake up by the end of today, they were going to clink him off.

The little turtle looked at the clock, which now read 11:45.

Splinter was similarly staring at the clock. For the past few days, Raphael, Donatello, and Michelangelo had been constantly blaming themselves. They didn't show it, but he knew. But they shouldn't be. He had been the one to kill their leader. If he had told Leonardo about his instability sooner, this all wouldn't have happened.

Before he had died, everything was running smoothly. Everyone was sure that he would survive, and the operation was going well. He himself had been planning to apologize after he had sufficiently healed. But of course, the chance never came. He knew that everyone made mistakes, and especially if it was a friend or family member, it was easy to forgive. Usually when someone was hurt, it was because the mistake-maker didn't tell him what happened, not for the mistake itself.

But this was different. What was bothering him was that he had caused his son's death and had never been able to apologize for it. Why? Because he hadn't even been there when he died! He hadn't been able to stand with the other three, hadn't been there to hold his hand, and hadn't been there to hear his last words.

_Leonardo, I'm so sorry. What kind of father am I?_

That was when he heard Donatello yell, "RAPH! MIKEY! MASTER SPLINTER! COME HERE, YOU HAVE TO SEE SOMETHING!" Splinter immediately got up and ran into the lab.

The time was 11:59.

When Raph raced into the lab, he nearly fainted. His older brother was sitting up, looking around. When he finally placed his eyes on the red banded turtle, he was already enveloping him in a hug, along with the other three members of the Hamato Clan. "I thought you were gone, I thought you died…I thought that we would have to go on without seeing your face ever again…" he whispered.

"To be honest, I thought so too," was the reply.

After all the excitement and emotion had passed, Donnie's genius side turned itself on again. "But you died! How is this possible… I'll have to study on this." As the rest of the Hamato Clan rushed around the leader, the genius gave him one last smile before retreating into his lab.

And after a solid day, none of them were surprised to hear Donnie screaming, "EUREKA! I FOUND IT! EVERYONE COME OVER HERE I NEED TO TELL YOU SOMETHING!" And naturally, everyone came rushing in.

"Guys, I finally discovered what made Leo come back to life! So I looked deeper into spiritual science, and I found out there were two lives: Spiritual and physical. Our physical lives are the lives that we try to protect every day. Our spiritual lives, however, end when our strings are cut. Since a person is born with one spiritual and one physical life, the number of lives we have of each type is equivalent, right?"

Everyone nodded, although no one except Master Splinter had fully understood what he had said. Even though Donatello highly suspected this, he continued.

"Anyway, so what I noticed was that when Leo had his strings snapped, his spiritual life ended. But when Raph brought him back to normal, (here's the important part), he grew back another spiritual life. So in other words, Leo had one physical life, but two spiritual lives, since he used one up and grew back another. That's when he got stabbed, and he used up the single physical life he had. However, remember what I said before, that the number of lives we have of both types have to be equivalent? That's where the logic comes in. He started out with one of each life, then lost the spiritual one. Then he got another spiritual one, but lost his physical. However, if he had been using 2 spiritual lives and only one physical life, he should get another physical life, because this way the number of lives he had of each type is the same, right? Two and two."

With this, the genius looked at them expectantly. Fortunately, three of them seemed to understand. Meanwhile, Mikey looked at him blankly. "What?" Groaning, Raph bonked him on the head. "Ow! What!?" Leo decided to end the confict before it progressed into a miniature war. "It's nothing, Mikey."

"How come you guys always say that?"

_3 weeks later_

Raphael burst into the room. "Sensei's given us permission to let him train a bit!" Donatello immediately countered this. "No way, he's going to start studying, if anything." Michelangelo quickly jumped in. "Nuh-uh, we're getting started on the video games!" Leonardo, not wanting for them to argue about _his _activities for the day, interrupted. "Guys, maybe you should calm down…"

Their father was in the dojo. Somewhere during the second week, he had called Leo over and apologized to him. The leader had accepted the apology, and then they had moved on to discuss about his recovery. Those few minutes, although brief, had been more important to him that he suspected his son would ever know.

Master Splinter sighed as he listened to his sons argue.

But this time, he was smiling.


End file.
